The present invention relates in general to a car heater for warming the passenger cabin of a motor vehicle, and more particularly to a passenger cabin heating system of a type which uses warmed coolant of the engine cooling system as its heat source.
Hitherto, there has been proposed an internal combustion engine of which cooling is effected by a boiling liquid cooling system. As will become apparent hereinafter, the cooling system basically features an arrangement wherein the coolant in the coolant jacket defined in the engine proper is permitted to boil and the gaseous coolant thus produced is passed out to an air cooled heat exchanger or condenser, and the coolant thus condensed and liquefied in the condenser is then recirculated back into the coolant jacket of the engine. Due to the effective heat exchanging carried out between the gaseous coolant in the condenser and the atmosphere, the cooling system exhibits a very high performance in cooling the engine.